Final answer:
The Greek term for 'rule by one' is monarchy, which was a form of government in ancient Greece where a single ruler held absolute power.
Step-by-step explanation:
The Greek term for 'rule by one' is monarchy. In ancient Greece, a monarchy was a form of government in which a single ruler, known as a monarch, held absolute power. The word 'monarchy' is derived from the Greek words 'monos' meaning 'alone' and 'arkhein' meaning 'to rule'.
Learn more about Greek monarchy